Enzymes
The reactant of a reaction catalysed by an enzyme
Substrate
The disruption of a molecule’s structure by an external factor such as heat
Denature
A membrane-bound organelle only found in plant and photoautotroph cells that is the site of photosynthesis
Chloroplast
An enzyme involved in initial carbon fixation during the light-independent stage of photosynthesis
Rubisco
The part of an enzyme where the substrate binds
Active site
The hindrance of an enzyme by blocking the active site and preventing the substrate from binding
Competitive inhibitor
Stage of photosynthesis where light energy splits water molecules into oxygen and hydrogen inside the thylakoid membranes
Light-dependent stage
Plants that minimise photorespiration by separating initial carbon fixation and the remainder of the Calvin cycle over space
C4 plants
The structure formed when an enzyme and substrate are bound together
Enzyme-substrate complex
The point at which for a given condition (e.g. temperature), the maximum function of an enzyme occurs.
Optimal condition
A coenzyme that is a proton (H+) and electron carrier in photosynthesis
NADPH
Plants that minimise photorespiration by separating initial carbon fixation and the remainder of the Calvin cycle over time
CAM plants
A change in the three-dimensional shape of macromolecules such as proteins
Conformational change
Changes in temperature, pH and concentration
Factors that affect enzyme action
Stage of photosynthesis where carbon dioxide is used to form glucose in the stroma of a chloroplast
Light-independent stage
A wasteful process in plants initiated by Rubisco that limits photosynthesis
Photorespiration
The energy required to initiate a reaction
Activation energy
A region on an enzyme that is not the active site
Allosteric site
Glucose, NADP+, ADP + Pi, water
Outputs of the light-independent stage of photosynthesis
Enzyme involved in initial carbon fixation in C4 plants
PEP carboxylase